KR100459986B1 - Advanced Step Aeration with Media(ASA, SFC-Biofilter) - Google Patents

Abstract

The present invention relates to a water treatment apparatus for the treatment of sewage or sewage, and more particularly, inflow of water inflow step by step, and by removing the nitrogen and phosphorus at the same time by varying the position and reaction conditions of each reactor, the installation of the device at the same time It relates to a step inlet nitrogen, phosphorus treatment apparatus using a carrier that can minimize the area and remove odor generated during water treatment.

The step inflow nitrogen and phosphorus treatment apparatus of the present invention is a bioreactor for biologically filtering the inflow water (sewage or sewage), and the inflow water is introduced into the reaction tank step by step. It is installed separately and re-aeration tank is installed after anoxic tank, and the order of bioreactor is anaerobic sludge tank → anaerobic tank → aerobic tank → anaerobic tank → re-aeration tank → final sedimentation cell.

Description

Advanced step aeration with media (ASA, SFC-Biofilter) using carrier

The present invention relates to a water treatment apparatus for the treatment of sewage or sewage, and more particularly, inflow of water inflow step by step, and by removing the nitrogen and phosphorus at the same time by varying the position and reaction conditions of each reactor, the installation of the device at the same time The present invention relates to a step inflow nitrogen and phosphorus treatment apparatus using a carrier which minimizes the area and removes odor generated during water treatment. Generally, sewage altitude treatment methods are more effective for high concentration sewage treatment. It is very difficult to increase the high treatment effect for low concentration sewage with high inflow of water and groundwater due to inadequate water quality and yield. Most of the conventional sewage altitude treatments have been applied to the circulation method. That is, after passing through an anaerobic tank into which raw water is introduced, an anaerobic tank to agitate the mixed liquid discharged from the anaerobic tank, and an aerobic tank (aeration tank) to introduce air to the mixed liquid discharged from the anaerobic tank through the micro-acid pipe, the liquid discharged from the aerobic tank is finally Separated into solid and liquid in the settling basin, the solid (precipitated sludge) is introduced into the anaerobic tank again and the liquid (supernatant, highly treated water) is discharged. This circulation method has a structure in which a pump is attached to an aerobic tank to circulate the mixed liquid in the aerobic tank again to a certain amount of an oxygen-free tank. In other words, the mixed liquid in the aerobic tank (aeration tank) has been circulated back to an oxygen-free tank (DO # 0) to remove nitrogen through denitrification. Most of the advanced sewage treatment methods are circulating and the nitrogen removal rate remains at 50 to 70%. In addition, it is difficult to stabilize the anaerobic tank or the aeration tank, so the removal rate remains at 50 to 70%. It is difficult to satisfy the conditions of each reactor as well as excessive power costs during circulation, and maintenance costs are high. In addition, the influent flows from the inlet at the same time, which inevitably increases the volume of the reactor.The circulation method is difficult to meet anoxic conditions and has a high power cost (the circulation ratio is usually about 2Q), limiting nitrogen removal (50 to 70%). There was a problem that it is difficult to meet the water quality standards when the ratio of nitrogen contained in the influent is high. In addition, since phosphorus removal also introduces the entire amount of the inflow water into the anaerobic tank or the anaerobic tank, the volume of the entire water treatment apparatus becomes large, and it is difficult to stabilize the conditions of each reaction tank, so that there is a problem that a sufficient removal effect is not obtained as the removal rate is about 50 to 70%. In addition, in winter, sludge swelling (Builking), etc. had a problem that adversely affects the treated water quality.To compensate for this disadvantage, research and development of highly active sludge variations by circulation have been conducted by various researchers. However, there is little or no removal of nitrogen and phosphorus in the standard activated sludge method or the circulating advanced treatment system.

Therefore, the present inventors have improved the existing standard sludge method and developed a new advanced treatment system to maximize the removal of nitrogen and phosphorus, which are eutrophic agents such as appeal, river algae, and red tide of the sea, and try to eliminate bulking. In addition, it is possible to cope with the odor removal and the increase of the amount of treated sewage in the sewage treatment plant near the city center, while minimizing the volume of the water treatment system, while removing the organic substances such as BOD (biological oxygen demand) and SS (floating solids) and odor causing substances. The present inventors introduce inflow water (sewage or sewage) in stages to solve these problems at the same time, and improve the efficiency of nitrogen and phosphorus removal by adding microbial carriers at the same time as the arrangement of each reactor. To minimize the installation area and reduce power costs. The inflow and odor removal medium is completely different from the circulating method, which is a circulating method, and fixed at the first stage of the water treatment system (ie, bioreactor) (installed only if there is an odor problem). The formation of a large floc in the bioreactor of the process and the mounting of fibrous media (only when supplementation is needed due to lack of HRT) results in a low SVI value, resulting in excellent sludge settling concentration and suppression of bulking. It is to provide a water treatment apparatus that can.

1 is a system schematic diagram of a step inlet nitrogen, phosphorus treatment apparatus using a carrier according to a preferred embodiment of the present invention.

<Description of the code | symbol about the principal part of drawing>

One ; Oxygen free sludge tank 2; Anaerobic tank 3; Aerobic tank 4; Anaerobic

5; Reaeration tank 6,7; Microacid engine 8; Air lift pump

9; Final settler 10; Conveying sludge 11; Internal circulation

12; MediaI 13; Media II 14; Advanced treatment water

15; Surplus sludge 16; Biofilter 17; Water treatment

18; MF film

In order to achieve the above object, the present invention is a step inlet nitrogen, phosphorus treatment apparatus using a carrier for treating the influent by introducing the influent (sewage or sewage) step by step, the sludge (0.3) -0.5Q) is introduced, the oxygen-free sludge tank to be stirred by using a stirrer to remove nitrogen, phosphorus, organic matter in the sludge, the sludge and influent (0.7-0.8Q) stirred in the oxygen-free sludge tank is introduced together, Anaerobic tank for agitation by using a stirrer to release phosphorus and nitrogen in sludge by adsorption of easily decomposable organic matter in the inflow water, NH ₃ -N in the mixed liquid introduced from the anaerobic tank, NOx by organic oxidation Is converted to -N, and air flows through the microacid pipe into the mixed solution so that phosphorus excess and organic oxidation occur simultaneously. Inlet of aerobic tank, the anoxic tank, discharged from the anoxic tank to the mixing the mixture liquid and the step of flowing the influent (0.2~0.3Q) discharged from the aerobic tank, the action of nitrate stirred using a stirrer to remove in the form of nitrogen gas (N ₂₎ The mixed solution is introduced to remove the untreated organic matter and phosphorus from the shear reaction tank, and to secure the DO of the treated water to prevent the anaerobicization of the final sedimentation basin to prevent phosphorus elution and increase the sludge sedimentation, Re-aeration tank for introducing air through the micro-acid pipe, and the sludge from the mixed liquid introduced from the re-aeration tank, the lower settling sludge is returned to the oxygen-free sludge tank, the upper supernatant (highly treated water) is discharged According to a preferred embodiment, the oxygen-free sludge tank can remove the smell by using soil microorganisms. It further comprises a deodorizing carrier (Media I) containing soil microorganisms, the aerobic tank and the re-aeration tank to increase the concentration of microorganisms to shorten the HRT of the device and to remove the nitrogen, phosphorus, and floating organic matter A microbial attachment carrier (Media II) is further included to maintain the microorganisms. According to another preferred embodiment, the reaeration tank is a membrane so that some of the treated water can be reused as the heavy water without having to secure a separate site. A filter membrane (MF membrane) is further included. According to another preferred embodiment, a biofilter is further included to filter the supernatant introduced from the final settler. According to the present invention, a circulating air lift pump for conveying a certain amount in the mixed liquid from the reaeration tank to the anoxic tank to increase the removal rate of nitrogen and phosphorus is The step inflow nitrogen and phosphorus treatment apparatus of the present invention is a bioreactor for biologically filtering influent water (sewage or sewage), and inlet water is introduced into the reactor in stages, and an aerobic tank is installed at the anoxic tank tip. The anaerobic sludge tank is separately installed at the end of the anaerobic tank and the reaeration tank is separately installed at the rear end of the anaerobic tank. The water treatment apparatus is called "Advanced Step Aeration (ASA)" in the sense that the water treatment apparatus has been developed and improved in a SA (Step Aeration) system. The "ASA" apparatus may additionally install a circulating air lift pump in the reaeration tank to return a certain amount of the mixed liquid in the reaeration tank from the reaeration tank to the anoxic tank. And while removing the source of odor and at the same time shortening the HRT (hydraulic retention time) of the reactor was configured to obtain a stable treated water quality while reducing the reactor volume. That is, an oxygen-free sludge tank (stabilization tank) installed in front of the "ASA" device is installed with a deodorizing carrier (Media I) containing soil microorganisms to remove odors using soil microorganisms, and an aerobic tank (aeration tank). ) And reaeration tanks are equipped with a microbial attachment carrier (Media II) to increase the concentration of microorganisms to shorten the HRT (hydraulic residence time) of the device and to maintain high removal rates of nitrogen, phosphorus, and suspended organics. . In the sense that the carrier was added to the "ASA" device, the inventors named such a device as "Advanced Step Aeration With Media" (ASAM). This ASAM device is not only low and high concentration sewage treatment but also existing activated sludge method or circulation. In addition to maximizing the removal efficiency of nitrogen and phosphorus, which are the causes of poor nutrition, the BOD, SS, and odor-causing substances can be removed by the advanced treatment method.In addition, the MF membrane (membrane filter membrane) can be removed in the reaeration tank of this 'ASA' device. ) Was deposited so that a portion of the treated water was re-usable as heavy water. In the sense that the MF membrane was added to the "ASA" apparatus, the inventors named such an apparatus "ASAMF". In addition, the inventor modified the operating conditions of the water treatment apparatus to shorten the BOD and SS removal time. At the same time, a biofiltration device was additionally installed at the rear of the final settler to filter the supernatant (highly treated water) discharged from the final settler. This is a very economical heavy water system. The water treatment system of the above water treatment system is stabilized in a stabilization tank (anoxic sludge tank), forms a floc in an anaerobic tank, an aerobic tank, an anoxic tank, a reaeration tank, precipitates in a final settler, and the biological in the last biofilter (biofilter). In the sense of filtration, the present inventors named such a water system as "SFC (Stabilization Flocculation Clarification) -Biofilter". Hereinafter, the water treatment apparatus of the present invention will be described with reference to the accompanying drawings. Is a system schematic diagram of a step inlet nitrogen and phosphorus treatment apparatus using a carrier according to a preferred embodiment of the present invention. Referring to FIG. Sludge (0.3Q) is introduced into the oxygen-free sludge tank (1) to the denitrification reaction to remove nitrogen. That is, in the oxygen-free sludge 1, the sludge is stirred using a stirrer to remove nitrogen, phosphorus, and organic matter in the settling sludge (conveying sludge) introduced from the final settler 9. The anaerobic tank 2 is an oxygen-free sludge tank 1 ) And the sludge and inflow water (0.2-0.3Q) stirred for a certain time are introduced together and stirred for a certain time. Influent is sewage or sewage. In the anaerobic tank, phosphorus release and nitrogen in the sludge are adsorbed and removed using readily biodegradable organics in the influent. In the aerobic tank (3), air is introduced into the mixed solution from the anaerobic tank through the microacid pipe. 'Abandon' means 'to introduce air', and 'gigi-jo' is called 'gigi-jo' in other words. In the aerobic tank, NH ₃ -N and organic nitrogen are converted to NOx-N by nitrification reaction, and phosphorus excess intake and organic substance oxidation occur simultaneously. The next reaction tank, the anoxic tank (4), is mixed with the mixed liquid flowing from the aerobic tank (3). Mix and stir the influent (0.2-0.3Q). In the anoxic tank 4, nitrates are removed in the form of nitrogen gas (N ₂ ) by using influent sewage as an organic carbon source for denitrification. At this time, if the soluble BOD (biological oxygen demand) in the influent sewage used as carbon energy is largely removed, ammonia nitrogen is synthesized in vivo. In other words, the sewage introduced into the anaerobic tank 4 is utilized as a carbon source to increase the denitrification effect and reduce the power cost since there is no circulation. Thus, the influent (sewage or sewage) is anaerobic tank 2 (0.7 to 0.7). 0.8Q) and anoxic tank 4 (0.2-0.3Q) have the advantage of reducing the volume of the reaction tank. The mixed liquid passed through the anoxic tank is introduced from the reaeration tank 5. In the reaeration tank 5, air is introduced through the microacid engine for a predetermined time. The reaeration tank 5 is a process for removing the untreated organics and phosphorus from the shear reaction tank and preventing the anaerobicization of the final sedimentation basin by securing DO of the treated water, thereby improving phosphorus re-dissolution prevention and sludge sedimentation. The liquid discharged from (5) flows into the final settler (9). The final settler is a reaction tank that separates the liquid introduced from the reaeration tank into a solid (ie sediment sludge) and a liquid. The lower settling sludge tank is returned to the anaerobic sludge tank 1, and the upper supernatant water (highly treated water) is discharged. An additional circulation air lift pump 18 may be installed in the reaeration tank 5 to return a certain amount of the mixed liquid in the reaeration tank from the reaeration tank to the anoxic tank. That is, the conveying sludge of the final settler 9 is anoxic sludge tank. (1) Anaerobic tank (2), anaerobic tank (2), anaerobic tank (4), anaerobic tank (4), reaeration tank (5) After forming a large floc by controlling the reactor's stirring speed, the sedimentation rate was increased in the final settler (9) (SVI 60 ~ 100 or less), and the supernatant water was passed through a biofilter to use the treated water as a heavy water. In the case of a small area, the MF membrane 18 was installed in the reaeration tank 5 so that a part of the treated water could be used as the heavy water. The ASA system is an anaerobic sludge tank (1), an anaerobic tank (2), and an aerobic tank ( 3) to anoxic tank (4), reaeration tank (5), final settler (9) The influent sewage is divided into anaerobic tank (2) and anoxic tank (4), and the step inflow treatment is carried out, and the MLSS concentration is 2,000 mg / L to 4,000 mg / L, and the return sludge ratio (0.3 to 0.5Q) is used. (Humanological residence time) 1 hour in the anaerobic sludge tank (1), 1 to 1.5 hours in the anaerobic tank (2), 1.5 to 2.5 hours in the aerobic tank (3), 1.5 to 2 hours in the anaerobic tank (4), reaeration tank ( The removal rate of TN, TP, BOD, COD, and SS was 8-95%, 90-95%, 95%, 95%, 95% or more when the HRT was 8 hours in 5 hours at 5 hours. In order to further shorten the HRT of the ASA system and to further enhance the effect of the treated water quality at low temperatures, an ASAM device having Media II (13) installed in the aeration tank (3) and the reaeration tank (5) was developed. Table 1 is a processing characteristic table of the ASAM system apparatus in which the ciliary filter medium of the present invention is installed in the aerobic tank 3 and the reaeration tank 5 when the HRT is 6 hours. ITEM Influent (mg / L) Effluent (mg / L) Removal rate BOD 200 to 350 10 to 20 More than 95% COD _Mn 100 to 250 8 to 16 More than 95% SS 90 to 300 7-12 More than 95% TN 40 to 80 5.4 to 13 85 to 95% or more TP 4.0 to 8.0 0.4 to 0.6 90-95% or more As mentioned above, ASAM method can improve eutrophication in effluent water with treatment efficiency of BOD, SS, COD more than 95%, TN 85-95%, TP 90-95% in HRT 6 hours. The MF membrane 18 was installed in the reaeration tank 5, which is a process, and a part of the treated water was reused as heavy water to develop an ASAMF device capable of producing high quality water. SFC-Biofilter method, which is a heavy water system with the addition of the SFC-Biofilter method, can be used for operation.In other words, the sludge of the final settler 9 is returned to stabilize the activated sludge in the stabilization tank 1, and then the amount of inflow water Q While stirring the anaerobic tank (2) and the aerobic tank (3) at 40 rpm, the agitation of the anaerobic tank (4) and the reaeration tank (5) at 30 rpm was maintained in the anaerobic tank (2) to the reaeration tank (5). After passing the time to 37 minutes in total, the final settler 9 (retention time 1.7 hours) was After passing through Biofilter (16) (EBCT 22.5 minutes), the treated water can be reused.In this case, the MLSS concentration of oxygen-free sludge tank (1) is 1,000 to 1,400 mg / L, DO 0.5 to 2 mg / L, HRT 1 hour (return sludge). 0.3-0.5Q 3 hours), anaerobic tank (2), aerobic tank (3), anaerobic tank (4), reaeration tank (5) MLSS concentration 450-700 mg / L HRT 37 minutes, MCRT 3 days, final settling precipitation time 1.7 After passing through the final Biofilter (16) (mediator: Geocarbon: particle size: 1-4mm, depth: 1-2m) with EBCT 22.5 minutes, the total amount of time required to recycle the treated water (medium water) with high quality treatment water 3 It could be secured in a short time of -4 hours.

The present invention as described above can be minimized the land area due to the step inflow, and when using as a water-based device, biofilm filtration can be installed at the rear end to contribute to the expansion of water resources by using the treated water as water-based water, and appeals to the taste of the treatment plant. In case of occurrence, oxygen-free sludge tank (1) can be filled with Media I (12) to remove odor-causing substances, and if the nitrification rate in winter is reduced or the retention time of bioreactor is not easy, ) And reaeration tank (5) can be filled with Media II (13) to improve the nitrogen removal efficiency, thereby improving eutrophication in the effluent.

Claims (4)

As a step inlet nitrogen, phosphorus treatment apparatus using a carrier for treating the influent by introducing the influent (sewage or sewage) in stages, Precipitated sludge conveyed from the final settler 9 (0.3-0.5Q) flows in, and the oxygen-free sludge tank 1 which is stirred by using an agitator to remove nitrogen, phosphorus and organic matter in the sludge, The sludge stirred in the oxygen-free sludge tank (1) is introduced together with the inflow water (0.7 to 0.8Q), and is stirred using a stirrer to release phosphorus and adsorb and remove nitrogen in the sludge using an easily decomposable organic material in the inflow water as an energy source. Anaerobic tank (2), NH ₃ -N, organic nitrogen in the mixed solution introduced from the anaerobic tank (2) is converted to NOx-N by nitrification reaction, so that phosphorus excess intake and organic matter oxidation occurs at the same time, the micro-acid pipe (6) Aeration tank (3) for introducing air through Oxygen-free tank (4) to mix the mixed liquid discharged from the aerobic tank (3) and the inflow water (0.2 ~ 0.3Q) introduced into the step, using a stirrer to remove nitrate in the form of nitrogen gas (N ₂ ), By introducing the mixed solution discharged from the oxygen-free tank (3), to remove the untreated organic matter and phosphorus in the shear reaction tank, to prevent the anaerobic of the final sedimentation basin through the DO of the treated water to prevent phosphorus elution and sludge sedimentation Re-aeration tank 5 for introducing air through the fine acid pipe (7) to the introduced mixed liquid to increase, and Precipitating sludge in the mixed liquid introduced from the re-aeration tank (5), the lower settling sludge is returned to the oxygen-free sludge tank (1), and includes the final settling battery (9) for discharging the upper supernatant water (highly treated water) , The oxygen-free sludge tank 1 includes a deodorizing carrier (Media I, 12) containing soil microorganisms to remove odors using soil microorganisms, The aeration tank and the reaeration tank may include a microorganism attachment carrier (Media II, 13) to increase the microbial concentration to shorten the HRT of the apparatus and maintain the removal rate of nitrogen, phosphorus, and suspended organic matter with high efficiency. A step inlet nitrogen, phosphorus treatment apparatus using a carrier to. delete The method of claim 1, In order to reuse some of the treated water as heavy water without having to secure a separate site, the reaeration tank 5 is introduced using a carrier, which further comprises a membrane filter membrane (MF membrane) 18. Mold nitrogen, phosphorus treatment equipment. The method of claim 1, Step inflow type nitrogen, phosphorus treatment apparatus using a carrier, characterized in that it further comprises a biofilter (biofilter, 16) to filter the supernatant water flowing from the final settler (9).